The Office for Nuclear Regulation will prosecute EDF Energy and Doosan Babcock after a roof fall at the Hinkley Point B nuclear plant left a worker with a cracked vertebrae.
The Doosan Babcock worker suffered the injury in April 2017 after he fell through a skylight while walking on the Somerset power station.
The ONR served both EDF and Doosan Babcock with an improvement notice last July, after an investigation exposed gaps in compliance of legal requirements by both parties in their approach to working at height at Hinkley Point B.
EDF will be prosecuted for offences under the Health and Safety at Work Act, while Doosan Babcock will be prosecuted for offences under Work at Height Regulations.
The incident was a conventional health and safety matter, the ONR said, adding that there was no radiological risk to the work.
Proceedings are scheduled to commence at Bath Magistrates Court on 12 September.
An EDF spokeswoman said: “We are reviewing the charges against us and considering our response.
“As we would in any industrial safety incident of this nature, we have and will continue to co-operate fully with the ONR.”
A Doosan Babcock spokeswoman said: “Health and safety is our number one value at Doosan Babcock and we take our responsibilities with regards to this extremely seriously.
“Following an industrial safety incident, involving a fall from height of a Doosan Babcock colleague at Hinkley Point B in April 2017, we have cared for our employee and have co-operated fully with the ONR throughout the investigation and we now acknowledge their intention to prosecute.
“As legal proceedings are pending we will not make any further comment at this stage.”